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In this study, cuticular wax load, its chemical composition, and biosynthesis, was studied during development of wild type (WT) bilberry fruit and its natural glossy type (GT) mutant. GT fruit cuticular wax load was comparable with WT fruits. In both, the proportion of triterpenoids decreased during fruit development concomitant with increasing proportions of total aliphatic compounds. In GT fruit, a higher proportion of triterpenoids in cuticular wax was accompanied by a lower proportion of fatty acids and ketones compared to WT fruit as well as lower density of crystalloid structures on berry surfaces. Our results suggest that the glossy phenotype could be caused by the absence of rod-like structures in GT fruit associated with reduction in proportions of ketones and fatty acids in the cuticular wax. Especially CER26-like, FAR2, CER3-like, LTP, MIXTA, and BAS genes showed fruit skin preferential expression patterns indicating their role in cuticular wax biosynthesis and secretion.

Aerial surfaces of plants are covered by a waxy cuticle protecting plants from excessive water loss and UV light. In the present study, composition and morphology of cuticular waxes of northern wild berry species bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), bog bilberry (V. uliginosum L.) and crowberry (Empetrum nigrum L.) were investigated. Scanning electron microscopy (SEM) revealed differences in epicuticular wax morphology, and gas chromatography–mass spectrometry (GC–MS) analysis confirmed variation in chemical composition of cuticular waxes between the berry species. The dominant compounds in bilberry and lingonberry cuticular waxes were triterpenoids, while fatty acids and alkanes were the dominant ones in bog bilberry and crowberry, respectively. Wax extracted by supercritical fluid extraction (SFE) from industrial press cakes of bilberry and lingonberry contained linoleic acid and γ-linolenic acid as the dominant compounds. Furthermore, in vitro sun protection factor (SPF) of berry waxes depicted good UV-B absorbing capacities.

Stellite-6 coatings were deposited onto AISI 304 stainless steel substrate by gas-fueled HVOF spraying, systematically varying the process parameter settings. By operating the HVOF torch with a fuel-rich mixture, dense coatings (<1% porosity) are produced, containing up to ≈3 vol% oxide inclusions. A substantial amount of a Cr-rich f.c.c. phase is found, mainly produced by quenching of molten lamellae, and distinct from the equilibrium, Co-based f.c.c. solid solution retained in unmelted particles. These coatings exhibit pseudo-passive behavior and survive 5 cycles (100 h) of the Corrodkote test (ASTM B380-97) with no substrate corrosion. Coatings obtained from oxygen-rich mixtures, on the other hand, contain fewer oxide inclusions but also greater porosity, and do not protect the substrate against corrosion. The wear behavior of the coatings is less influenced by deposition conditions. In ball-on-disk dry sliding tests, all coatings exhibit wear rates of 2-3 × 10⁻⁵ mm³/(N·m), higher than those reported for bulk or clad Stellite, because of interlamellar delamination. Strain-induced, “martensitic” phase transformation from the f.c.c. structure to a h.c.p. one is observed over a 1-2 μm depth below the contact surface. Additional tribo-oxidation is onset when frictional heat dissipation has heated the wear debris enough to trigger its reaction with the environment. Correspondingly, a transition to a regime of higher friction occurs (from ≈0.6 to ≈0.8). At 400 °C, lamellar delamination is suppressed but wear rates rise to 5-8 × 10⁻⁵ mm³/(N·m) because of abrasive and adhesive wear. At 800 °C, a dense “glaze” tribofilm is formed by sintered debris particles, firmly bonded to a thermally grown oxide scale on the underlying metal surface. The “glaze” protects the coating, lowering the wear rate to ≈1 × 10⁻⁵ mm³/(N·m) and the friction coefficient to <0.45. Under high-stress particle abrasion conditions, wear rates of ≈1 × 10⁻³ mm³/(N·m) are found.

Summary. Background: Volumetric capnography is technically more demanding but theoretically more performant than the time-based alveolar deadspace fraction (PaCO(2)-EtCO(2))/PaCO(2) as bedside diagnostic tool for ruling-out pulmonary embolism (PE) in outpatients. Objective: We compared both diagnostic accuracies, combined to clinical probability evaluation, in patients with a suspicion of PE and positive ELISA D-dimer results. Patients and methods: In this clinical multicenter trial with prospective inclusion and three-month follow-up, alveolar deadspace fraction was compared by ROC analysis with other parameters derived from volumetric capnography. Results: Capnography was performed in 239 patients, of which 205 tests (86%) were conclusive. The prevalence of PE was 33%. The ROC curve analysis for alveolar deadspace fraction was 0.73+/-0.04. The diagnostic performances of parameters from volumetric capnography were not significantly better. 16% (95% CI 12%-21%) of patients presented a (PaCO(2)-EtCO(2))/PaCO(2) ratio under the cut-off value of 0.15 with a low clinical probability. This combination excluded PE with a sensitivity of 96% (95% CI 89%-99%) and a negative likelihood ratio of 0.17 (95% CI 0.09-0.33). Conclusion: Volumetric capnography failed to achieve better performances than the alveolar deadspace fraction (PaCO2-EtCO2)/PaCO2 for excluding PE in outpatients with positive D-dimers. Future studies should clarify the safety of ruling out PE in patients combining a low clinical probability with positive D-dimers and a (PaCO2-EtCO2)/PaCO2 ratio under the cut-off value of 0.15.

Objective: To study the long-term effects of selegiline in monotherapy and in combination with levodopa in the early phase of Parkinson disease (PD). Methods: One hundred fifty-seven de novo PD patients were randomized in a double-blind, placebo-controlled study of 7 years' duration. In the monotherapy part, selegiline significantly delayed the initiation of levodopa therapy vs placebo. The authors now report the results from the combination part of the study, in which 140 patients received selegiline or placebo in addition to individually tailored levodopa therapy. Results: Compared with placebo, selegiline slowed the progression of disease disability as measured by the Unified Parkinson Disease Rating Scale (UPDRS) total score (p = 0.003) or by motor (p = 0.002) and Activities of Daily Living (p = 0.0002) subscores. After 5 years in combination therapy, the mean difference in the UPDRS total score was nearly 10 points, with patients receiving placebo having 35% higher scores. Simultaneously, patients receiving placebo needed progressively higher doses of levodopa than patients receiving selegiline, after 5 years, the mean dosage of levodopa was 19% higher with placebo than with selegiline (p = 0.0002). Considering the entire (monotherapy and combination therapy) 7-year study time, there was a trend for selegiline to delay the start of wearing-off fluctuations (hazard ratio 0.55, p = 0.08). In both phases of the study, selegiline was safe and well tolerated. Conclusions: The results of this long-term study confirm earlier findings indicating that selegiline delays the progression of the signs and symptoms of Parkinson disease. Copyright © 2006 by AAN Enterprises, Inc.